/* Copyright 2013-2015 www.snakerflow.com.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.snaker.engine.parser;

import java.util.List;
import org.snaker.engine.model.NodeModel;
import org.snaker.engine.model.TransitionModel;
import org.w3c.dom.Element;
import cn.hutool.core.util.XmlUtil;

/**
 * 抽象dom节点解析类 完成通用的属性、变迁解析
 * 
 * @author yuqs
 * @since 1.0
 */
public abstract class AbstractNodeParser implements NodeParser {
    /**
     * 模型对象
     */
    protected NodeModel model;

    /**
     * 实现NodeParser接口的parse函数 由子类产生各自的模型对象，设置常用的名称属性，并且解析子节点transition，构造TransitionModel模型对象
     */
    public void parse(Element element) {
        model = newModel();
        model.setName(element.getAttribute(ATTR_NAME));
        model.setDisplayName(element.getAttribute(ATTR_DISPLAYNAME));
        model.setLayout(element.getAttribute(ATTR_LAYOUT));
        model.setPreInterceptors(element.getAttribute(ATTR_PREINTERCEPTORS));
        model.setPostInterceptors(element.getAttribute(ATTR_POSTINTERCEPTORS));

        List<Element> transitions = XmlUtil.getElements(element, NODE_TRANSITION);
        for (Element te : transitions) {
            TransitionModel transition = new TransitionModel();
            transition.setName(te.getAttribute(ATTR_NAME));
            transition.setDisplayName(te.getAttribute(ATTR_DISPLAYNAME));
            transition.setTo(te.getAttribute(ATTR_TO));
            transition.setExpr(te.getAttribute(ATTR_EXPR));
            transition.setG(te.getAttribute(ATTR_G));
            transition.setOffset(te.getAttribute(ATTR_OFFSET));
            transition.setSource(model);
            model.getOutputs().add(transition);
        }

        parseNode(model, element);
    }

    /**
     * 子类可覆盖此方法，完成特定的解析
     * 
     * @param model
     * @param element
     */
    protected void parseNode(NodeModel model, Element element) {

    }

    /**
     * 抽象方法，由子类产生各自的模型对象
     * 
     * @return
     */
    protected abstract NodeModel newModel();

    /**
     * 返回模型对象
     */
    public NodeModel getModel() {
        return model;
    }
}
